Abstract
By means of89Y nuclear magnetic resonance (NMR) spectra direct evidence of staggered magnetization induced by a uniform field has been obtained in the Heisenberg antiferromagneticS = 1 chain Y2BaNi1−xMgxO5. A correspondence between the resonance lines and the lattice positions is established, providing an image of the alternating magnetic moments that develop around the Mg impurities at the chain boundaries. The amplitude of these moments is found to decrease exponentially from the edges, with a characteristic decay distance equal to the magnetic correlation length numerically evaluated for an infinite chain. While the magnetization pertaining to ions far from the boundaries behaves as in typical gapped systems, the edge spins exhibit anS = 1/2 Curie-like deviation. These results promote the NMR approach to access the spin-spin correlation function in antiferro-magnetic quantum spin systems at finite temperatures.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
